{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T05:10:00Z","timestamp":1789017000578,"version":"build-2803163510"},"reference-count":41,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T00:00:00Z","timestamp":1788825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62305400"],"award-info":[{"award-number":["62305400"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["62305400"],"award-info":[{"award-number":["62305400"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006407","name":"Natural Science Foundation of Henan Province","doi-asserted-by":"publisher","award":["252300421234"],"award-info":[{"award-number":["252300421234"]}],"id":[{"id":"10.13039\/501100006407","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Key Projects of Science and Technology of Henan Province","award":["262102321067"],"award-info":[{"award-number":["262102321067"]}]},{"name":"Young Talent Support Program of Henan Association for Science and Technology","award":["2025HYTP055"],"award-info":[{"award-number":["2025HYTP055"]}]},{"name":"Key Scientific Research Projects of Higher Education Institutions in Henan Province","award":["27ZX025"],"award-info":[{"award-number":["27ZX025"]}]},{"name":"Discipline Young Master's Tutor Cultivation project of Zhongyuan University of Technology","award":["SD202432"],"award-info":[{"award-number":["SD202432"]}]},{"award":["SD202432"],"award-info":[{"award-number":["SD202432"]}],"id":[{"id":"https:\/\/ror.org\/0360zcg91","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Natural Science Foundation of Zhongyuan University of Technology","award":["K2026ZD007"],"award-info":[{"award-number":["K2026ZD007"]}]},{"award":["K2026ZD007"],"award-info":[{"award-number":["K2026ZD007"]}],"id":[{"id":"https:\/\/ror.org\/0360zcg91","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Graphene quantum dots (GQDs) with distinct optical responses were prepared from pyrene using urea, melamine, and 2,4-pyridinedicarboxylic acid as nitrogen-containing regulators and were subsequently combined with ZIF-8 for visible-light-driven CO2 reduction. FT-IR, Raman, XRD, optical spectroscopy, representative high-magnification transmission electron microscopy, and X-ray photoelectron spectroscopy (XPS) showed regulator-dependent structural, compositional, and optical differences. XPS detected surface nitrogen in all three GQD samples, with the highest N content in y-GQDs, while the relative N 1s component distributions differed across the series. At a nominal 4 wt% GQD addition, r-GQDs\/ZIF-8 gave the highest observed mean CO and CH4 formation rates of 23.51 \u00b1 0.48 and 4.08 \u00b1 0.15 \u03bcmol\u00b7g\u22121\u00b7h\u22121, respectively, corresponding to approximately 2.9- and 4.5-fold increases over pristine ZIF-8. This sample also showed the lowest fitted charge-transfer resistance, the highest mean photocurrent density, and the fastest qualitative time-resolved photoluminescence decay among the compared composites. Across three independent five-cycle tests, 83.78 \u00b1 0.54% of the initial combined CO and CH4 rate was retained. These results establish correlations among regulator identity, surface composition, optical relaxation, photoelectrochemical response, and catalytic activity, but do not determine a unique charge-transfer pathway or exclude contributions from surface basicity, CO2 adsorption, and nominal-loading differences.<\/jats:p>","DOI":"10.3390\/nano16181126","type":"journal-article","created":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T13:46:33Z","timestamp":1788875193000},"page":"1126","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of Nitrogen-Containing Regulators on Graphene Quantum Dot\/ZIF-8 Composites for Photocatalytic CO2 Reduction"],"prefix":"10.3390","volume":"16","author":[{"given":"Lei","family":"Wang","sequence":"first","affiliation":[{"name":"College of Materials Electronics and Energy Storage, Zhongyuan University of Technology, Zhengzhou 450007, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyuan","family":"Gao","sequence":"additional","affiliation":[{"name":"College of Materials Electronics and Energy Storage, Zhongyuan University of Technology, Zhengzhou 450007, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shang","family":"Li","sequence":"additional","affiliation":[{"name":"College of Materials Electronics and Energy Storage, Zhongyuan University of Technology, Zhengzhou 450007, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuangyan","family":"Li","sequence":"additional","affiliation":[{"name":"College of Materials Electronics and Energy Storage, Zhongyuan University of Technology, Zhengzhou 450007, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2738-007X","authenticated-orcid":false,"given":"Weitao","family":"Li","sequence":"additional","affiliation":[{"name":"College of Materials Electronics and Energy Storage, Zhongyuan University of Technology, Zhengzhou 450007, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"28618","DOI":"10.1039\/D4TA04600E","article-title":"Artificial CO2 photoreduction: A review of photocatalyst design and product selectivity regulation","volume":"12","author":"Fu","year":"2024","journal-title":"J. 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